Does the Certainty of Arrest Reduce Domestic Violence? Evidence from Mandatory and Recommended Arrest laws

Domestic violence remains a major public policy concern despite two decades of policy intervention. To eliminate police inaction in response to domestic violence, many states have passed mandatory arrest laws, which require the police to arrest abusers when a domestic violence incident is reported. These laws were justified by a randomized experiment in Minnesota which found that arrests reduced future violence. This experiment was conducted during a time period when arrest was optional. Using the FBI Supplementary Homicide Reports, I find mandatory arrest laws actually increased intimate partner homicides. I hypothesize that this increase in homicides is due to decreased reporting. I investigate validity of this reporting hypothesis by examining the effect of mandatory arrest laws on family homicides where the victim is less often responsible for reporting. For family homicides, mandatory arrest laws appear to reduce the number of homicides. This study therefore provides evidence that these laws may have perverse effects on intimate partner violence, harming the very people they seek to help.